Modelling clusters of galaxies by f(R)-gravity

TL;DR

This paper explores whether f(R)-gravity can explain galaxy cluster masses and gravitational potentials without dark matter, using weak field limits to fit observed data.

Contribution

It demonstrates that f(R)-gravity's corrected potential can account for galaxy cluster masses without dark matter, linking cluster size to interaction lengths.

Findings

f(R)-gravity fits observed cluster masses without dark matter

Cluster sizes depend on interaction lengths of potential corrections

Potential provides a good match to X-ray estimated visible matter

Abstract

We consider the possibility that masses and gravitational potentials of galaxy cluster, estimated at X-ray wavelengths, could be explained without assuming huge amounts of dark matter, but in the context of $f(R)$-gravity. Specifically, we take into account the weak field limit of such theories and show that the corrected gravitational potential allows to estimate the total mass of a sample of 12 clusters of galaxies. Results show that such a gravitational potential provides a fair fit to the mass of visible matter (i.e. gas + stars) estimated by X-ray observations, without the need of additional dark matter while the size of the clusters, as already observed at different scale for galaxies, strictly depends on the interaction lengths of the corrections to the Newtonian potential.